In the operation of hydraulic and pneumatic systems, it is necessary to use a device for the storage of pressure fluid. Such a device, commonly known as a "pressure accumulator", serves to smooth out the variations in the pressure in a fluid system by receiving fluid at a time of high pressure and discharging it at a time of low pressure; this seems to maintain the flow of fluid at a generally constant value in the same way that a capacitor operates in an electrical system. In some cases the accumulator consists of a piston moveable in a cylinder, the movement being resisted by a coil spring; this type has the deficiency of having a tendency to leak. Some versions of the piston-type accumulator have used diaphragms to prevent the leakage, but the diaphragms used in this way tend to bind and tear. Furthermore, the need for precision-fitting pistons and cylinders makes the cost of the accumulator quite high and prevents its use in inexpensive installations where the presence of such a device could be very useful. These and other difficulties experienced with the prior art devices have been obviated in a novel manner by the present invention.
It is, therefore, an outstanding object of the invention to provide a pressure accumulator for use in inexpensive fluid systems.
Another object of this invention is the provision of a pressure accumulator making use of the excellent elastic properties of natural rubber.
A further object of the present invention is the provision of a pressure accumulator that does not require accurate piston-cylinder surfaces and in which most of the parts can be produced by deep-drawing of sheet metal.
It is another object of the instant invention to provide a pressure accumulator which is simple in construction, inexpensive to manufacture, and which is capable of a long life of useful service with a minimum of maintenance.
It is a further object of the invention to provide a pressure accumulator which does not use a mechanical spring and which has a novel manner of guiding the piston and cylinder without providing them with finely finished surfaces.
It is still a further object of the present invention to provide a pressure accumulator which is capable of accommodating to a substantial amount of misalignment of the parts.
With these and other objects in view, as will be apparent to those skilled in the art, the invention resides in the combination of parts set forth in the specification and covered by the claims appended hereto.